Ratchet mechanism.



PATENTED APR. 26, 1904.

Ci E. MITCHELL.

RATGHET MECHANISM.

APPLICATION nun 001'. 7, 1903.

2 SHEETS-SHEET 1.

N0 MODEL.

Tm: nonms vucns 00. PHoTou'n-kn, WASHINGTON n. :4

PATBNTED APR. 26', 1904.

APPLIOATION PIDED 001. 7, 1803.

U0 MODEL.

UNITED STATES Patented April 26, 1904,

PATENT OFFICE.

CHARLES E. lVHTCHELL, OF NEW BRITAIN, CONNECTICUT.

RATCHET MECHANISM.

SPECIFICATION forming part of Letters Patent NO. 758,329, dated l-Iprii 26, 1904.

Application filed October 7, 1903.

To all whom it may concern..-

Be it known that I, CHARLns ELLIOTT MrrcH- ELL, a citizen of the United States, residing at New Britain, county of Hartford, and State of Connecticut, have invented certain new and useful Improvements in Ratchet Mechanism, of which the following is a full, clear, and exact description.

My invention relates to ratchet mechanism especially adapted for screw-drivers and other toolsfor example, bits, drills, and boringtools in general.

It is my object to improve and simplify the mechanisms heretofore devised for this purpose and to provide a finished device which is simple, durable, strong, and effective.

In the accompanying drawings, Figure 1 is a side elevation of my invention as applied to an ordinary bitbrace, the chuck and a portion of the brace being shown in side elevation, while the pawl-carrying member is shown in section. In this figure the pawl-carrying member is in position to couple the driving part solidly with the driven part to prevent the independent rotation of either. Fig. 2 is a similar view, the pawl-carrying member being shown in a position to secure a right-hand drive. Fig. 3 is a similar view, the pawl-carrying member being in a position to secure a left-hand drive. Fig. 4 is a side elevation of the operating-sleeve detached. Fig. 5 is a vertical sectional view of the parts in the position that they appear in Fig. 1. Fig. 6 is a similar View, the parts being in the position that they appear in Fig. 2. Fig. 7 is a similar view, the parts being in the position that they appear in Fig. 3. Fig. 8 is a horizontal sectional View on the plane of the line 8 8, Fig. 5. Fig. 9 is a plan view of the cam for moving the pawl-carrying member. Fig. 10 is a perspective View of said cam. Fig. 11 is a plan view of the pawl-carrying member. Fig. 12 is a view of the under side of said pawl-carrying member. Fig. 13 is a side elevation of the pawl-carrying member.

1 is a tool-holding device of any suitable construction-for example, that of the ordinary chuck used in connection with bit-braces. The part 1 constitutes the driven part.

2 is a portion of the bit-brace which may af- Serial No. 176,048. (No model.)

ford one convenient means of applying power. The part 2 constitutes the driving part.

3 is a shaft or spindle which is suitably connected with the tool-holder 1 so that when the former is turned the latter will turn with it. One end of the brace 2 may be enlarged to form a tubular housing 21, the upper end of which may be contracted at 22 to form a bearing for the spindle 3. The lower part of said housing 21 is sleeve-like and may take a bearing upon a shouldered enlargement 31 at the base of the spindle 3. By this construction it will be observed that there is a space between the spindle 3 and the inner wall of the part 21, in which space the pawl-carrying member and the spring hereinafter described may be located. On the upper face of the shouldered enlargement 31 is formed or locateda crownratchet 32. The sleeve-like lower end of the housing 21 is provided with oppositely-ar ranged slots 23 24, extending up and down,

and these slots perform the function hereinsame to be moved thereonfor example, from' the position shown in Fig. 6 to the position shownin Fig. 7 or to the position shown in Fig. 5.

41 42 are radial lugs carried by the member 4, said lugs projecting through the slots 23 24 and outside of the housing '21.

The pawl-carrying member 4 is preferably provided on the upper end with a slight ledge 43. One end of the spring 5'bears against said member 4 around said ledge,-while the other end may bear against the inner upper end 22 of the housing 21. This spring 5, as shown, is an expansion-spring. On the lower side of the'member 4 are two sets of oppositely-arranged pawls 44 45. In the drawings I have shown two pawls in eachset; but obviously the number of pawls in each set is immaterial. These pawls 44 45 are located adjacent to the radial lugs 41 42, respectively.

The pawls 44 45 are oppositely faced, and

pawls may be permitted to engage with said same to permit the driven part 1 to berotated" in one direction only.

To operate the pawl-carrying member 4 so as to interlock the driving and driven parts or so as to permit only a right-hand or a lefthand drive to the latter, as may be desired, I provide a cam 7, which may have a central stop 71 and oppositely-arranged inclines extending upwardly from the base of the same. In these inclines I preferably provide notches 7 2 7 2 7 3 74. The cam 7 surrounds and is rotatably mounted on the lower sleeve-like extension of the housing 21, and the radial lugs 41 42 rest upon the cam-surface of said device 7 6 is an outer protective casing, which may also constitute the handle portion of the operating device. This sleeve 6 is secured to the operating-cam 7, and its outer surface may be knurled to permit the operator to readily turn the same.

33 is a head which may be secured in any convenient manner to the spindle 3 outside the housing 21 to secure the parts together.

The parts are so proportioned that when the pawl-carrying member 4 is level and the lugs 41 42 rest in the cam-notches 7 2 the oppositely-faced pawls 44 45 will simultaneously engage the crown-ratchet 32 and lock the driving and driven parts together. When power is applied through the member 21, the same is imparted directly to the lugs 41 42 of the pawl-carrying member, thence through the pawls 44 45 to the crown-ratchet, and thence to the tool-carrying member. When it is desired to rotate the driven part in a right-hand direction only, the operating-sleeve 6 is turned, rotating the cam 7 in such a manner as to tilt the pawl-carrying member 4 from the position indicated in Figs..1 and 5 to the position indicated in Figs. 2 and 6,wherein the lug 41 will rest in the high notch 73 and the set of pawls 44 will be held out of engagement with the crown-ratchet 32. Under these conditions the driving part 2 is coupled with the driven part only when the former is turned in the right-hand direction and uncoupled therefrom when the direction is reversed. Should the operator desire to secure a lefthand drive only, the sleeve 6 and the cam 7 are turned so as to tilt the pawl-carrying member 4 from the position indicated in Figs. 2 and 6 to the position indicated in Figs. 3 and 7, by which operation and in which position the pawls 45 are raised and held out of engagement with the crown-ratchet 32, while the pawls 44 are lowered into engagement with said ratchet. In this position the driving memher is coupled with the driven member only when the former is rotated in a left-hand direction. The spring5 at all times provides a yielding pressure upon the upper side of the pawl-carrying member 4, so as to cause the pawls thereon when permitted by the cam to yieldingly press against the face of the crownratchet 32.

It is to be understood that the oppositelyfaced pawls on the member 4 may comprise only a single pawl on each side or a plurality of pawls on each side, and I do not intend in the claims to limit myself by any language to any particular number of pawls on each side.

That I claim is 1. In a ratchet mechanism for screw-drivers and other tools, a driving part, a spindle rotatably connected therewith, a driven part, a pawl-carrying member rotatively mounted on said spindle, two oppositely-faced pawls carried by said pawl-carrying member, one of said pawls being arranged to couple said parts when the driver is rotated in one direction, the other pawl being arranged to couple said parts when the driver is rotated in the opposite direction, a connection between said pawl carrying member and one of the said'parts and means for operating said pawl-carrying member to free either of said pawls from the other part, whereby power may be transmitted from the driving part to the driven part to rotate it in one direction or the other, or to permit both of said pawls to simultaneously engage said other part to interlock the same against independent rotation.

2. In a ratchet mechanism for screw-drivers and other tools, a driving part, a driven part, said parts being rotatably connected, a pawlcarrying member carried by one of said parts and rotatable relatively thereto, oppositelyfaced pawls on said member arranged to alternately or simultaneously engage the other device and means I for holding said pawls in yielding engagement therewith, and means cooperating with said pawl-carrying member to tilt it to free the pawls on either side of said ratchet device from engagement, whereby power may be applied to the driven part to rotate it in one direction or the other, or

to interlock said driving and driven parts.

3. In a ratchet mechanism for screw-d rivers and other tools, a driving part, a driven part, said parts being rotatably connected with each other, a pawl-carrying member rotatably and loosely mounted upon said driven part, a

spring between said driving part and pawlcarrying member to press the latter into yielding engagement with said driven part, oppositely-faced pawls carried by said member, a crown-ratchet on said driven part arranged to receive said pawls, means for tilting said member to hold one or the other of said oppositely-faced pawls out. of engagement with said crown-ratchet, or to permit both sets of oppositely-faced pawls to engage said crown-ratchet, said member being itself in connection with the driving device at all times whereby the driven part may be coupled with the driving part when the latter is rotated in one direction or the other and freed therefrom when the direction of rotation of the driving part is reversed, or whereby the driving and driven parts may be interlocked against independent rotation.

4:. In a ratchet mechanism for screw-drivers and other tools, a driving part, a driven part, a housing on the driving part, a spindle on the driven part projecting through said housing, a chamber within said housing and around said spindle, an annular tilting pawl-carrying member located within said chamber and loosely mounted on said spindle, slots in the Wall of said housing and lugs projecting from the said member through said slots, means carried by said member for interlocking said driving and driven parts, or for connecting said parts when the driving part is rotated in one direction and disconnecting said parts when said driver is rotated in the opposite direction, and means for yieldingly pressing said member toward the driven part.

5. In a ratchet mechanism for screw-drivers and other tools, adriving part, a driven part, a housing carried by one of said parts, a spindle carried by the other part and rotatably connecting said driving and driven parts, a chamber within said housing and around said spindle, a tilting pawl-carrying member located within said chamber, means for holding said member from driving engagement relatively to one of the said parts when the driver is rotated in one direction, and for interlocking said parts to prevent the independent rotation of either, and a spring for yieldingly pressing said member into its engaging position.

6. In a ratchet mechanism for screw-drivers and other tools, a rotatable driving part, a driven part rotatably connected with said driving part, an annular pawl-carrying member intermediate said parts and means for holding said. member against independent rotation relatively to the driving part, oppositely-faced pawls on said member on the lower side thereof and arranged to simultaneously or alternately engage with the driven part to interlock the driving and driven parts against independent rotation or to couple said parts turned in the opposite direction, a rotatable cam carried by one of the said parts and arranged to operate said member, anda spring to press said member toward said cam and into engagement with the driven part.

'7. In a ratchet mechanism for screw-drivers and other tools, a rotatable driving part, a-

driven part rotatably connected therewith, a

crown-ratchet on said driven part, the latter couple said parts for rotation in one direction but not in a reverse dlrectlon, said member being always held against independent rotation relatively to the driving part.

8. In a ratchet mechanism for screw-drivers and other tools, a crown-ratchet, an annular pawl-carrying member to coact therewith carried by a spindle on said ratchet, oppositelyfaced pawls carried by said member. and a controlling-cam for engaging said member to move the same and to hold either pawl out of its operative position or to allow both pawls to assume an operative position.

9. In a ratchet mechanism for screw-drivers and other tools, a rotatable driving part, a driven part rotatably connected to said driving part, a crown-ratchet on said driven part intermediate its length, a bearing above and be low said ratchet, a movable pawl-carrying member adjacent to said ratchet, said member being incapable of rotation independently of the driving part, oppositely-arranged pawls on said member facing said ratchet device,

and means to move said member whereby,

direction.

CHARLES E. MITCHELL.

Witnesses:

R. C. MITCHELL, RoBT. S. ALLYN. 

